Alkenes bearing electron-withdrawing substituents are catalytically acetalized with 1,3-propanediol only by the use of PdCl2(MeCN)2 catalyst under O2 atmosphere. When a combination of BiCl3 and LiCl is used as co-catalyst, the acetalization proceeds effectively. These results indicate that a hydroperoxopalladium(II) species is most likely an active catalyst in the present reaction.